So you can purchase your ingredients and flavorings at these places:
Manufacturers:
The Flavor Apprentice - This is for all your TFA flavorings.
Capella Flavor Drops - Home page for CAP flavorings.
FlavourArt - This is the homepage for FA flavorings but is in ITALIAN. Setting up a North American site soon!
Inawera Flavours - For INW flavorings.
All in one flavor shops:
Bull City Vapor - This is my favorite place to get flavorings because of their great fucking prices and their amazing customer support. Also because I'm on the East Coast, so shipping is nice and quick
EcigExpress - This place is also one of my go to's for ingredients. I usually come over here when BCV is out of stock on something or just doesn't carry it. ECX has a VERY large inventory and you can usually get whatever you need here, though their prices aren't as good.
EliquidMart - This place has excellent prices on FA and CAP. The only issue with this place is they don't tell you if they have something in stock or not, so shipping can take much longer than expected.
WizardLabs - This is probably my last resort for flavorings, only because their prices aren't as good, and they sell their smalls in 8ml vials as opposed to 10ml drippers like the other places.